doc: sml: fast_pair: update for NCS v3.1.0

Updated the Software Maturity tables for the Google Fast Pair category
to align the documentation with the current status of nRF Connect SDK
v3.1.0 codebase.

Ref: NCSDK-34512

Signed-off-by: Kamil Piszczek <[email protected]>

Author: kapi-no

doc/nrf/releases_and_maturity/software_maturity.rst

@@ -2282,8 +2282,8 @@ The following table indicates the software maturity levels of the support for Go
             * - **Locator tag**
               - :ref:`fast_pair_locator_tag`
               - Experimental
-              - Experimental
-              - Experimental
+              - Supported
+              - Supported
               - Supported
       .. tab:: nRF91 Series
 
@@ -2396,10 +2396,10 @@ The following table indicates the software maturity levels of the support for ea
               - nRF54L10
               - nRF54L15
             * - **Initial pairing**
-              - Experimental
-              - Experimental
               - Experimental
               - Supported
+              - Supported
+              - Supported
             * - **Subsequent pairing**
               - Experimental
               - Experimental
@@ -2417,8 +2417,8 @@ The following table indicates the software maturity levels of the support for ea
               - Experimental
             * - **Find My Device Network extension**
               - Experimental
-              - Experimental
-              - Experimental
+              - Supported
+              - Supported
               - Supported
       .. tab:: nRF91 Series